Reaction Steps
To a stirred solution of (1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-3a-((1R,3S)-3-(4-ethylpiperazine-1-carbonyl)-2,2-dimethylcyclobutylcarbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysen-9-yl acetate (Example 69, 550 mg) in MeOH:THF (2:1) at 0° C. temperature 2N NaOH (4 mL) was added and allowed to stir at room temperature for about 16 hours. After completion of the reaction (monitored by TLC), the volatiles was evaporated, the aqueous layer was extracted with ethyl acetate and the organic layer was washed with water, brine and dried with Na2SO4. The solvent was evaporated and the resulting crude was stirred in hexane to get crude solid. The solid crude was purified over silica-gel column chromatography to afford the title compound. Wt: 200 mg, Yield: 93.3%. 1H NMR (300 MHz, CDCl3): δ 5.86 (d, 1H, J=8.1 Hz), 4.72 (s, 1H), 4.57 (s, 1H), 4.18-4.06 (m, 1H), 3.78-3.68 (m, 1H), 3.52-3.30 (m, 3H), 3.23-3.08 (m, 2H), 2.92-2.86 (m, 1H), 2.52-2.20 (m, 3H), 2.01-1.88 (m, 2H), 1.80-1.12 (m, 33H), 0.96, 0.93, 0.87, 0.81, 0.74 (s, 18H); Mass: [M+1]+ 649 (5%), [M+Na]+ 671 (100%); IR (KBr, cm−1): 3353, 2937, 2858, 1635, 1618, 1533, 1459, 1390, 1262, 1250, 1148, 1048, 1033, 1020, 983, 883; M.R: 177° C.-188.7° C.; HPLC: 95.72%.
